When you start a blog or even if you’ve had your blog for a while, there is a multitude of options for making your blog do things.
Trying hundreds of WordPress plugins myself over the last period and reading reviews  I’ve narrowed the list down to the very best that works for me:

SECURITY AND MAINTENANCE

Spam Protection

Akismet 

Akismet is the best-known anti-spam plugin for WordPress, mainly because it comes included in the default installation of WordPress since Akismet is developed by Automattic. The same company is responsible for developing and maintaining WordPress and for creating and developing plugins as powerful as Jetpack for WordPress.

Akismet protects both spambots and manual spam, consulting databases of IPs with low reputation and blocking some users who have a terrible reputation and are recognised in some way.
It is also necessary to point out that at the time Akismet was the only plugin compatible with two great plugins of widely used forms: Gravity Forms and Contact Form 7. The problem is that most anti-spam plugins currently support them, not to mention that Gravity Forms, as a Premium solution, brings its anti-spam method for bots.

After all these advantages, does it have any disadvantages? Yes.

I see the following disadvantages:

It’s not as light as Anti-spam or AntiSpam Bee because it requires a connection to external services to operate.
Some online complaints say that Akismet detects about 10 to 20% of the legit comments as SPAM, so it has a high rate of false positives.

You can find more information about Akismet for WordPress at the following URL: https://wordpress.org/plugins/akismet/
If you install a new WordPress using the official files, Akismet will be installed and activated by default when you access your new installation or website.

Backup

BackupGuard

A full backup plugin for WordPress that offers unlimited backup and restore options. This add-on can be extremely effective while you are migrating your site and will make the process super simple.

It offers you the option to schedule your backup at frequent intervals. You can set up an email notification when the backup is done; you can also download the backup files as needed.

This add-on can be handy to secure your website in WordPress completely. You can load your backup copies in Dropbox, Google Drive, and Amazon S3 automatically, which will save you a reasonable amount of time and money to manage your website.

Maintenance

Maintenance

This add-on allows you to close the website for maintenance, and enable 503 temporarily unavailable services. The plugin comes with a lot of features that include responsive design so that the web looks good on all types of devices.

Some other features of this WordPress plugin are user login with validation, upload your logo, the Google Analytics field, full-screen background, show or hide the administration bar, etc.

TRAFFIC GENERATION & SOCIAL SHARING

Social Auto Post

Blog2Social 

Automatically share and schedule your blog posts to social media customised for each network and planned for the best times to post to profiles, pages, and groups.

Free Features:

Connect profiles on Facebook, Twitter, VK.com, LinkedIn, Instagram, XING, Reddit, Pinterest, Flickr, Medium, Tumblr, Diigo, and Bloglovin.
Connect a business page on Facebook
Share your blog posts through all your selected networks
Use Facebook Instant Sharing to share your blog posts in Facebook profiles, pages, in groups and events!
Adapt your publications and add comments, tags, hashtags, drivers or emojis for each social network.
Manage all blog posts and share the blog posts of all users of your blog (administrator rights are required)
Select and share images with your posts
Track your posts on social networks with the publications control panel.
Re-share old posts
Generate Hashtags automatically from your WP tags
Use the integrated Bitly shortener. To track the performance of your links.
Cure content by sharing content from any source through all of your selected networks.

SUBSCRIBERS + COMMUNITY BUILDING

Contact Form 7

Contact Form 7 is one of the most popular WordPress plugins. Its objective is to create forms in a fast and efficient way. It’s free and is continuously updated.
Has become so popular that many theme developers recommend it. Some even integrate it into their theme with specific customisation according to the image and style of the template.
This plugin allows you to create very advanced contact forms, but it’s not as powerful as Gravity Forms or Formidable.
Because Contact Form 7 doesn’t save the fields in the database if by chance the message is lost along the way, either because of the server or the email service, the information simply disappears. If you want to avoid it and save the forms in the database, you can complement Contact Form 7 with Flamingo.

 Formilla Edge

Formilla Edge is a powerful messaging platform in the application and email to help you address customers with the right message at the right time using automation. There is also a popular live chat plugin from the same team so you can use both products for a full messaging suite that includes email, in-app and live chat.
You will be required to sign up for a Formilla account, and your 15-day Premium Free Trial begins. It offers a free account where you can store and manage contacts at no cost, and you can also create email collection widgets to increase your email subscribers. Even Facebook or Twitter widgets to increase your social followers. Sending emails and viewing smart messages in the application is only available with the Premium plan, unfortunately.

Newsletter

Unlimited subscribers with their corresponding statistics and unlimited emails with tracking. In terms of design, it has a configurable subscription, page or form widget, as well as customisable themes. It’s compatible with Postman mail configuration plugins, WP Mail SMTP, Easy WP SMTP, Easy SMTP Mail, and WP Mail Bank. It has a registration system that complies with European privacy laws. When you want to edit the emails, the editor has a text and HTML version.
The Newsletter configuration itself is not complicated and has a wide variety of options. Also, it can create multiple distribution lists in various languages. If you want to take it further, it also has paid add-ons if you’re going to look at the statistics or make it compatible with Woocommerce.